bnxt_en: Add bnxt_get_num_stats() to centrally get the number of ethtool stats.

Instead of duplicating the logic multiple times.  Also, it is unnecessary
to zero the buffer in .get_ethtool_stats() because it is already zeroed
by the caller.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

@@ -198,19 +198,23 @@ static const struct {
 
 #define BNXT_NUM_PORT_STATS ARRAY_SIZE(bnxt_port_stats_arr)
 
+static int bnxt_get_num_stats(struct bnxt *bp)
+{
+	int num_stats = BNXT_NUM_STATS * bp->cp_nr_rings;
+
+	if (bp->flags & BNXT_FLAG_PORT_STATS)
+		num_stats += BNXT_NUM_PORT_STATS;
+
+	return num_stats;
+}
+
 static int bnxt_get_sset_count(struct net_device *dev, int sset)
 {
 	struct bnxt *bp = netdev_priv(dev);
 
 	switch (sset) {
-	case ETH_SS_STATS: {
-		int num_stats = BNXT_NUM_STATS * bp->cp_nr_rings;
-
-		if (bp->flags & BNXT_FLAG_PORT_STATS)
-			num_stats += BNXT_NUM_PORT_STATS;
-
-		return num_stats;
-	}
+	case ETH_SS_STATS:
+		return bnxt_get_num_stats(bp);
 	case ETH_SS_TEST:
 		if (!bp->num_tests)
 			return -EOPNOTSUPP;
@@ -225,11 +229,8 @@ static void bnxt_get_ethtool_stats(struct net_device *dev,
 {
 	u32 i, j = 0;
 	struct bnxt *bp = netdev_priv(dev);
-	u32 buf_size = sizeof(struct ctx_hw_stats) * bp->cp_nr_rings;
 	u32 stat_fields = sizeof(struct ctx_hw_stats) / 8;
 
-	memset(buf, 0, buf_size);
-
 	if (!bp->bnapi)
 		return;
 
@@ -835,7 +836,7 @@ static void bnxt_get_drvinfo(struct net_device *dev,
 		strlcpy(info->fw_version, bp->fw_ver_str,
 			sizeof(info->fw_version));
 	strlcpy(info->bus_info, pci_name(bp->pdev), sizeof(info->bus_info));
-	info->n_stats = BNXT_NUM_STATS * bp->cp_nr_rings;
+	info->n_stats = bnxt_get_num_stats(bp);
 	info->testinfo_len = bp->num_tests;
 	/* TODO CHIMP_FW: eeprom dump details */
 	info->eedump_len = 0;